The authors compared circularly and linearly polarized lights in the ionization and fragmentation of anthracene, using 800 nm femtosecond laser pulses at intensities of 1013–1015 W cm−2. Singly and doubly charged intact molecular ions as well as numerous fragment ions were observed in the mass spectra, which were investigated as a function of laser intensity and polarization. At comparable intensities above the saturation threshold for complete ionization, the fragmentation pathways are enhanced with a circularly polarized field compared to a linearly polarized field. Resonant excitation of the molecular cation through the 2Au<--2Bg transition is proposed to be the initial step to ion fragmentation. The circularly polarized field interacts with a larger fraction of the randomly oriented molecules than the linearly polarized field, and this is considered to be the reason for the enhanced fragmentation brought about by circularly polarized light. ©2007 American Institute of Physics

DA - 19790629 IS - 0026-8925 (Print) LA - eng PT - Journal Article RN - 0 (DNA, Circular) RN - 56-75-7 (Chloramphenicol) RN - 59-01-8 (Kanamycin) SB - IM

DA - 19990429 IS - 0950-382X (Print) LA - eng PT - Journal Article RN - 0 (DNA, Circular) RN - 0 (Recombinases) RN - 0 (Viral Proteins) RN - EC 2.7.7.- (DNA Nucleotidyltransferases) RN - EC 2.7.7.- (Integrases) RN - EC 2.7.7.- (Transposases) RN - EC 2.7.7.- (excisionase) RN - EC 2.7.7.- (integron integrase IntI1) SB - IM

DA - 19991007 IS - 0021-9193 (Print) LA - eng PT - Journal Article RN - 0 (DNA Transposable Elements) RN - 0 (DNA, Circular) RN - 0 (DNA, Superhelical) RN - 0 (Viral Proteins) RN - EC 2.7.7.- (DNA Nucleotidyltransferases) RN - EC 2.7.7.- (Integrases) RN - EC 2.7.7.- (excisionase) SB - IM